Particulate silicon carbide is extensively used in abrasive and refractory applications. However, its use in the manufacture of structural elements by pressure sintering has not in all cases proven to be entirely satisfactory. One difficulty in the fabrication and use of high density, polycrystalline silicon carbide is that large grains are formed that reduce the strength to impractical levels. As a result conventional hot pressing of silicon carbide powder is incapable of producing structural components which must possess high strength and impact resistance, such as those found in the hot sections of air breathing propulsion systems.
It is an object of this invention, therefore, to provide a method of limiting grain growth during the fabrication of high density, polycrystalline silicon carbide articles.
Another object of the invention is to provide a method of fabricating silicon carbide articles which possess outstanding mechanical properties.
A further object of the invention is to provide an improved hot pressing method for forming silicon carbide structural components.
Other objects and advantages of the invention will become apparent to those skilled in the art upon consideration of the accompanying disclosure and the drawing, in which: